In reply to Pedro50:
Unless you're found to be really, really negligent, you're unlikely to be charged for a rescue from the JMT. The Forest Service, BLM and National Park Service all have an official policy of charging for rescues, but in practice for any reasonable callout they almost always absorb the costs into their operating budgets.
A much bigger concern in the US is the cost of healthcare and repatriation. As of March last year, there is now no single insurer in Australia who will underwrite rock climbing in North America, solely because of the hospital bills.
Will